您在此专栏后缺少逗号：

`p`.`name`请考虑以下查询：

SELECT i.itemtype AS Item

, p.name

, SUM(CASE

WHEN itemtype = 2148 THEN i.count

ELSE 0

END) AS Count

, SUM(CASE

WHEN itemtype = 2152 THEN i.count

ELSE 0

END) * 100 AS Count1

, SUM(CASE

WHEN itemtype = 2160 THEN i.count

ELSE 0

END) * 10000 AS Count2

FROM player_items AS i

LEFT JOIN players AS p ON i.player_id = p.id

WHERE i.itemtype IN (2148, 2152, 2160)

GROUP BY i.itemtype ASC

LIMIT 0, 30要将这三列合并在一起，您可以：

SELECT t.itemType AS Item, t.Count, t.Count1, t.Count2

, SUM(t.Count1, t.Count2, t.Count3) AS Total

FROM

(

SELECT i.itemtype AS Item

, p.name

, SUM(CASE

WHEN itemtype = 2148 THEN i.count

ELSE 0

END) AS Count

, SUM(CASE

WHEN itemtype = 2152 THEN i.count

ELSE 0

END) * 100 AS Count1

, SUM(CASE

WHEN itemtype = 2160 THEN i.count

ELSE 0

END) * 10000 AS Count2

FROM player_items AS i

LEFT JOIN players AS p ON i.player_id = p.id

WHERE i.itemtype IN (2148, 2152, 2160)

GROUP BY i.itemtype ASC

LIMIT 0, 30

) AS t或者您可以添加另一个CASE

SELECT i.itemtype AS Item

, p.name

, SUM(CASE

WHEN itemtype = 2148 THEN i.count

ELSE 0

END) AS Count

, SUM(CASE

WHEN itemtype = 2152 THEN i.count

ELSE 0

END) * 100 AS Count1

, SUM(CASE

WHEN itemtype = 2160 THEN i.count

ELSE 0

END) * 10000 AS Count2

, SUM(CASE

WHEN itemtype = 2148 THEN i.count

WHEN itemtype = 2152 THEN (i.count * 100)

WHEN itemtype = 2160 THEN (i.count * 10000)

ELSE 0

END) AS Total

FROM player_items AS i

LEFT JOIN players AS p ON i.player_id = p.id

WHERE i.itemtype IN (2148, 2152, 2160)

GROUP BY i.itemtype ASC

LIMIT 0, 30CASE statements使您无需运行另外三个SELECT语句来返回相同的结果。